Configuring The Keepalive Command; Vpdn Group Session Limiting; Pppoe Session Limiting; Monitoring Ppp Sessions Using The Snmp Management Tools - Cisco ASR1002 - ASR 1002 Router Software Configuration Manual

Configuring the Cisco ASR 1000 Series Router for High Scalability

VPDN Group Session Limiting

Using the Virtual Private Dialup Network (VPDN) Group Session Limiting feature, you can limit the
number of VPDN sessions allowed per VPDN group. VPDN session limits can increase performance and
reduce latency for routers that are otherwise forced to operate at high capacity.
For more information about VPDN Group Session Limiting, see the feature documentation at:
http://www.cisco.com/en/US/docs/ios-xml/ios/vpdn/configuration/xe-3s/vpd-tunnel-mgmt.html

PPPoE Session Limiting

The PPPoE Session Limit Support feature prevents the router from using too much memory for virtual
access by limiting the number of PPPoE sessions that can be created on a router or on all Ethernet
interfaces and subinterfaces as well as ATM interfaces and subinterfaces.
For more information about PPPoE session limiting, see the feature documentation at:
http://www.cisco.com/en/US/docs/ios-xml/ios/bbdsl/configuration/xe-3s/bba-limit-legcfg-xe.html

Monitoring PPP Sessions Using the SNMP Management Tools

To prevent the virtual access subinterfaces from being registered with the Simple Network Management
Protocol (SNMP) functionality of the router and using up the memory, do not use the SNMP
management tools of the router to monitor PPP sessions. Use SNMP views to isolate the bulk queries
and accidental requests.
Use the no virtual-template snmp command to disable the SNMP management tools:
Router(config)# no virtual-template snmp

Configuring the Access Interface Input and Output Hold Queue

The default value of Gigabit Ethernet and 10 Gigabit Ethernet interfaces is 375 packets for the input and
output hold queues. If the interfaces are required to handle a high rate of control packets, such as LCP,
IPCP, PPP, L2TP, and DHCP, the default value may not be sufficient. To ensure high scalability, set the
access interface input and output hold queue to 4096:
Router(config)# interface gig1/0/0
Router(config-if)# hold-queue 4096 in

Configuring the keepalive Command

For PPP sessions, the keepalive command sets the keepalive timer for a specific interface. To ensure
proper scaling and to minimize CPU utilization, set the timer for 60 seconds or longer. The default value
is 10 seconds:
interface Virtual-Template1
ip unnumbered Loopback1
keepalive 60
no peer default ip address
ppp authentication pap
Cisco ASR 1000 Series Aggregation Services Routers Software Configuration Guide
6
Broadband Scalability and Performance